Arthur f



(No Model.) A.P.L.BELL.

PROCESS OF BXTRAGTING AND REPINING ASPHALTUM, M.

NO. 505,416. PatentedlSgpt. 19, 1893 UNITED ST T PATENT OFFICE.

ARTHUR F. L. BELL, OF SAN FRANCISCO, CALIFORNIA, ASSIGNOR-TO THE CALIFORNIA PETROLEUM AND ASPHALT COMPANY, OF SAME PLACE.

PROCESS OF EXTRACTING AND REFINING ASPHALTUM, 80G.

SPECIFICATION forming part of Letters Patent No. 505,416, dated September 19, 1893.

Application filed February 2, 1893. Seiial No. 460,773. No specimens.)

tion.

My invention relates to that class of the above named substances which are found in nature, mixed or combined with sand, clay, silt, rock, dirt, or other similar vehicles or substances from which the asphalt, bitumen, pitch, oils, paraffine, 800., must be separated before being ready for commercial use. In various parts of America, and of other countries, there exist large deposits of asphalt, tumen, and the other oils and substances hereinabove designated, in which the said asphalt,

bitumen, oils, and other said substances are" found, not in a pure condition but mixed with and absorbed in a certain amountof sand, clay, silt, rock, dirt, or other vehicle, from which they must be separated before being merchantable, or valuable for commercial purposes. In many cases these deposits have been formed by the seepage of the asphalt, bitumen, oil, or other kindred substance from below through the shale or other substance underlying the deposit, and then percolating the sand, or other vehicle, and saturating it to a greater or less degree. In other deposits these asphalts, bitumens, oils, or other kindred substances, have come to the surface of the earth in the form of springs, and have .overflowed and spread out, covering and sinking down into the surrounding earth, sand, clay, rock, or other vehicle, and soaking it, sometimes to a depth of many feet, sometimes to a depth of but a few inches. Similarly, in the Island of Trinidad, is found a large lake of pitch from which the crude material known as Trinidad lake pitch or Trinidad lake asphalt is brought in large quantities to the United Statesand is here refined for the purpose of separating the asphalt, bitumen, or

impregnated. Accordingly, two processes have been chiefly attempted and used for the purpose of separating the asphalt, bitumen, or other kindred substances, from the silt, sand, earth, 850. In the first of these two processes the crude material from the deposits is placed in iron tanks, or kettles, and heated by the application of heat to the kettle. Asthe mass becomes more heated it becomes thinner and more fluid, and there results a certain loosening of the cohesion between the asphalt (or other kindred substances) and the sand or earthwhich had been contained in it; and the sand, rock, silt, or other vehicle, being heavier than the asphalt, bitumen, pitch, oil (or kindred substances) the latter would tend to rise to the top of the heated mass in the kettlc,leaving the sand, earth, rock, or other vehicle, at the bottom and the asphalt (or other kindred substances)- could then be removed from the upper portion; of the kettle. This process, though much used, has many serious defects. In the first place, the application of heat to a degree sufficient, and for a period long enough, to liquidize the materials in the kettle and to effect a separation, as above described, drives off from the mass many of the In the second place,-

complete by this process, since the heated material always remains sufficiently viscous and thick to retain in itself, even on the top of the kettle, a considerable portion of the sand or other impurities which should be gotrid of. In the third place, the process is'an expensive and laborious one, requiring careful heating, to prevent its burning, and requiring the laborious removal of the asphalt from the top of the kettle and, afterward, of the earth, sand, 850., from the bottom of the kettle. And, finally, the process is a wasteful one, since a large amount of asphalt, bitumen, oil, &c., remains mixed with the earth, sand, silt, &c., at the bottom of the kettle and is lost when the latter is taken out and thrown away.

A second process which has been attempted for the purpose of separating these asphalts and other materials from the sand, or other vehicle, containing them, has been to place the raw material in an open kettle containing water and heating the mass up to or near the boilingpoi-nt of the water. By this process, as in the one above described, the asphalt (or kindred substances) was loosened and softened so as to separate and loosen from the sand, or other vehicle, and to rise to the top of the water, inasmuch as the specific gravity of these asphalts, bitumens, pitches, oils and kindred substances when raised to a tern peratureof that approaching boiling water, is less thanthat of the water. A better separation of the asphalt from the sand is effected by this hot water process than by the process above-described; but there are some serious defects in this process. It islaborious and expensive, because intermittent, andrequiringthe cleaning out of the kettle every few hours for the purpose of removing the silt, sand, ($50., from the bottom. Moreover the asphalt (or kindred substance) which, in this process, rises to the top of the water and is removed-from there, always absorbs within itselfduring this process, a large amount of theiwater which then has to be removed from theasphalt, 850., before thelatter is-ready for commercial use; and no economical or efficient method of removing this water has heretofore been found or used. Wherever this hot water process of separation has been used, the attempt has heretofore been made to drive off the water from the asphalt, &c., (after the latter has been removed from the hot water tank) by boiling the mixture of the asphalt with the water contained in it, in another tank or vessel, whereby the water passes off in steam, leaving the asphalt, bitumen, oil (or kindred substances) behind. This. method of separating the water from the asphalt is,

however, veryimperfect and defective. It isexpensive in requiring the application of heat for along period of time, and in requiring that the-mixture, during this final process of boiling, be carefully watched and stirred to avoid burning, and it is in the end, an imperfect process, since it drives off, with the steam, a portion of the lighter and more volatile oils which are essential and necessary to the commercial value and usefulness of the refined product.

My invention which is designed to overcome the defects of all of the foregoing processes. and to effect an economical, speedy and complete separation of'the asphalt, bitumen, pitch, oil, &c., from the sand, rock, earth, silt, or other substances containing them, consists of, first, heating the crude material of the deposit in water to a temperaturesufficient to loosen the cohesion between the asphalt, bitumen, pitch, &c., and the rock, sand, silt, &c., containing them, and sufficient to raise the specific gravity of the asphalt (or kindred substances) above that of the water, whereby the asphalt (or kindred substances) separates from the sand, clay, earth, or other foreign material, and floats upon the surface of the water and may be removed from there;

and, second, in subjecting the asphalt (or kindred substances) after its removalfrom the surface of the water, as-aforesa1d,:to centrifugal action, whereby, on account of the difference between the specific gravity of the said asphalt (or kindred substances) and the water, the asphalt (or-kindred substances) is separated from the water with which it had become largely impregnated while being separated, in the first instance, from the sand,

rock, silt, or other vehicle; third, in so controlling the temperature of theasphalt (or kindred substances) after itsfirst removal from the surface of the Water, and prior to and during its centrifugal separation from the water within it, as to make the specific gravities of the said asphalt (or kindred substances) and of the water contained in it, sufficiently'different to make a centrifugal separation of the two possible; and, fourth, in economizing heat and materials by return: .ing the water, when centrifugallyseparated from the asphalt (together with any asphalt, bitumen, &c., which may have passed off with the water in the centrifugal separation) to the tank or bath in which the first separation fromthe sand, silt, 850., occurred; and, fifth, in so arranging the tank (in which the separation of the asphalt, &c., from thesand, &c., occurs) or machinery for the centrifugal separation, and the mechanism by which the materials and products are fed and conveyed, as to permit of the whole process of separation being carried on continuously and economically.

In the accompanying drawing I show one form of apparatus in which my process is carried out and applied, though it is to be understood that my invention is not confined to this particular apparatus and that the processes claimed and invented by me may be used with various other forms of apparatus and machinery.

Referring to said drawing, the figure is'a view of the apparatus, the parts of which are shown in vertical section.

A is a tank having at one end a receiving compartment a which communicates below, but not at the top, with the main body of the tank A. The contents of the tank A can be heated by any suitable means, as by fire applied directly to the bottom or outside of the IOC tank, or by a steam jacket, or as here shown by steam pipes H H entering the tank. In the lower portion of the tank is mounted a worm conveyer or screw B, covered with a screen I). The conveyer is driven by a shaft 0, to which suitable power from without is applied. The inner end of the conveyer is in communication with the receiving compartment at, and its outer end communicates with a bucket elevator F. From the upper portion of the tank A issues a chute or spout G with a jacket 19. The spout G is in communication with a drum Imounted in a casing K, saiddrum being upon a shaft J to which rotary motion is applied by suitable means, as by the pulleyj and beltj'.

L is a compartment in the drum, separated by a diaphragm Z from the main compartment of drum 1, and communicating with the main compartmentP, by openings 1 near the drum. With this compartment L communicates a pipe M, and with the main compartment P of the drum communicates a pipe N. Surrounding the drum I is a jacket 19'.

The process as carried out in this apparatus is as follows:--The asphaltum, mineral pitch, bitumen, Trinidad lake pitch, petroleum, pe-

troleum oil, parafline, paraffine oil, or other kindred substance, is delivered, in its crude state, into the compartment a of the tank A, falls upon the near end of the screw-conveyer B, and is slowly carried along by the latter toward the bucket elevator F. In the tank A, water is placed to about the level of the line W W; and steam is admitted through the pipes H H to heat the water to the required degree. During the time of its passage through the conveyer B, the material is in contact with the water (which reaches it through the open ends of conveyer B and through the perforations in the screen Z9); and as the motion of the screw conveyer B drives the material along, the latter is continually broken up and changed in position, and is readily reached in all its parts by the Water around it. As the material in conveyer B reaches the requisite temperature, the asphalt bitumen, or pitch, &c., becomes softened and liquid, its cohesion to the particles of sand, earth, silt, the, becomes lessened, its specific gravity becomes less, until it has astrong tendency to rise to the surface of the water; and it separates from the sand, or other vehicle, rises in the water through the perforations in screen I) and floats on the top of the water. The Velocity of the revolution of the conveyer B is made such that there will be sufficient time for the asphalt, pitch, &c., to be completely separated in this manner, from the sand, silt, &c.,before it reaches the end of the conveyor, so that none of the crude material remains in the conveyer at its end, except the sand, silt, &c., which is to be got rid of, and which, being heavier than the water, remains at the bottom. This sand, silt, &c., is forced out by the conveyer into the elevator F. The asphaltic materials, after rising to the surface of the water in tank A, and being then impregnated or saturated with water, are permitted to flow off through the spout G into the drum I, where the centrifugal separation of the water from the asphalt (or other kindred substance) occurs.

To understand the method of separation in the drum I, it must be noted that the specific gravity of these asphaltic substances materially changes and lessens, as the temperature is raised; and that, while some of these substances are at the ordinary temperatures, of

say 50 or lighter than water, and others are, at those temperatures, heavier than water, all become much lighter than water when the temperature is raised to 212, or thereabout. The process of separating the asphalt, &c., from the water, by means of the drum I, is equally effective whether the asphalt, &c., is lighter or heavier than the water when in the drum I; but, in the two cases,

the separation occurs in converse methods. I

As the drum I is rapidly revolved the heavier of the two materials (whether the water or the asphalt) will separate from the lighter material and will be thrown to the periphery of the drum, from which it is forced up into the compartment L and from thence, under the pressure behind, it passes out through the pipe M. The lighter material (whether the water or the asphalt) is also thrown outwardly but to a less extent than the. heavier, and is confined to a zone inside that of the heavier material and is forced up through the pipe N. Accordingly, in using this process, if the asphalt which we are handling is onewhich, at normal temperatures, is lighter than water, or if, with any kind of asphalt material, we pass the asphalt immediately from the surface of the Water in tank A into the drum I, while the mass is still quite hot, in that case the asphalt (or kindred substance) will pass through the pipe N and be received in suitable receptacles, while the water (being the heavier) will passthrough the pipe M, by which it is conveyed (with any residue of as.- phalt or oils remaining in it) back to the tank A; and for separation of this last kind, Where the asphalt is lighter than the water, we keep the spout G and the drum I, and its connecting parts, heated by jackets p and p or other means, so as to accentuate the difference 1n the specific gravities of the water and of the asphalt materials; and the return of this water to the tank A through the pipe M, results in a saving both of water and of heat. If, on the other hand, we are dealing with an asphalt which, at ordinary temperatures, is heavier than water, and permits the mass to cool after taking it from the tank A and before passing it into the drum 1, then, before reaching the drum I, the asphalt (or kindred substance) will have lost the buoyancy which caused it while hot to float in the tank A and will have become heavier than water, and during the separation in the drum, it will be the asphalt which will pass out through the pipe M, while the water will pass out through the pipe N and be returned to the tank. In using the apparatus in this last method, the spout G and drum I could be cooled by jackets so as to accentuate the difference in the specific gravities of the materials to be separated, just as in the former method they could be heated.

The accompanying drawings are arranged for this latter method.

The process of separating the refined material, as above described, first from the sand, earth, or silt, with which it is found mixed in nature, and next from the Water absorbed by it in the first separation, is rapid, economical and complete, and may be carried on by such apparatus as above described, or by an equivalent arrangement, constantly and continuously, and is a great improvement on any of the processes heretofore used for said purpose.

Having thus described my invention, what I claim as new, and desire to secure by Letters Patent, is

1. The improvement in the process of extracting and refining asphaltum, mineral pitch, bitumen, Trinidad lake pitch, petroleum, petroleum oils, paraffine, parafline oils, and kindred substances, which consists first, in heating in water and keepingin motion the material with its carrying sand, or vehicle, whereby the former separates from the sand, or vehicle, and rises and floats on the surface of the water, and then in discharging the carrying sand, or vehicle, and subjecting the material to be refined, to centrifugal force, whereby it is separated from the water with which it became impregnated in the process of separation from the sand, or vehicle, substantially as described.

2. The improvement in the process of extracting and refining asphaltum, mineral pitch, bitumen, Trinidad lake pitch, petroleum, petroleum oils, paraffine,paraffine oils, and kindred substances, which consist first in heating in water the material with its carrying sand, or vehicle, whereby the material to be refined separates from the sand, or vehicle, and rises to and floats on the surface of the water, then in subjecting the material to be refined to centrifugal force whereby it is separated from the water with which it became impregnated in the process of sepacontinuous flow of the material with its carrying sand, or vehicle, whereby the material separates from the sand, or vehicle, and rises to and floats on the surface of the wa ter, and then in subjecting thematerial to be refined to centrifugal force, whereby it is separated from the water with which it became impregnated in the process of separation from the sand, or vehicle, the separation of the ma terial from the sand or vehicle, and the transfer of the water impregnated material to and its separation from said water by centrifugal force, being a continuous operation, whereby the process may be carried on continuously with a constant supply and discharge, substantially as described above.

4. The improvement in the process of extracting and refining asphaltum, mineral pitch, bitumen, Trinidad lake pitch, petroleum, petroleum oils, paraffine, paraffiue oils, and kindred substances, which consists, first, in heating in water the material with its carrying sand, or vehicle, whereby the material separates from the sand or vehicle and rises and floats on the surface of the water, and then in subjecting the material to be refined, to centrifugal force, whereby it is separated from the water with which it became impregnated in the process of separation from the sand, or vehicle, and of constantly keeping the material at a temperature to produce a substantial difference between the specific gravities of the material itself and of the water contained in it, so as to make possible a separation of the two by centrifugal action, substantially as above described and for the uses and puposes set forth.

In witness whereof I have hereunto set my hand.

ARTHUR F. L. BELL. Witnesses:

S. H. NoURsE, GEO. H. STRONG. 

